Information by Business Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Segment Reporting Information [Line Items]
Consolidated operating revenues	$ 55,907	$ 26,745	$ 116,780	$ 125,465
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	15,710	(3,899)	15,650	(2,506)
Total Assets	652,715		652,715		661,291
Residential real estate
Segment Reporting Information [Line Items]
Consolidated operating revenues	23,358	16,592	53,424	40,802
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	248	(3,663)	(3,373)	(18,817)
Total Assets	259,723		259,723		272,210
Commercial real estate
Segment Reporting Information [Line Items]
Consolidated operating revenues	4,102	1,450	11,195	2,345
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	(142)	(523)	1,167	(5,295)
Total Assets	73,002		73,002		67,650
Rural land sales
Segment Reporting Information [Line Items]
Consolidated operating revenues	18,889	517	23,377	3,342
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	14,666	307	16,849	2,204
Total Assets	8,449		8,449		10,048
Forestry
Segment Reporting Information [Line Items]
Consolidated operating revenues	9,558	8,186	28,784	78,976
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	3,709	2,593	9,609	57,090
Total Assets	50,816		50,816		58,638
Other
Segment Reporting Information [Line Items]
Consolidated income (loss) from operations before equity in (loss) of unconsolidated affiliates and income taxes	(2,771)	(2,613)	(8,602)	(37,688)
Total Assets	$ 260,725		$ 260,725		$ 252,745